HomeFreshwater aquarium fishGuppies & livebearersRelict splitfin Relict splitfin (Xenoophorus captivus) Scientific name: Xenoophorus captivus Hubbs, 1924 The Relict splitfin (Xenoophorus captivus) is a freshwater fish of the family Goodeidae. In the aquarium it needs water at 18–26°C (64–79°F). Native range: North America, Panuco River system, Mexico. Relict splitfin care at a glanceTemperature18–26°C (64–79°F) BiologyOccurs in algal-laden waters. Feeds on algae.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameXenoophorus captivusFamilyGoodeidae (Splitfins)OrderCyprinodontiformes (Live bearers, Killifishes and Rivulines)ClassActinopterygii (Ray-finned fishes)Maximum length5.0EnvironmentFreshwater;; pH range: 7.0 - 7.8; dH range: 10 - 25 demersalClimateSubtropicalDistributionNorth America: Panuco River system, Mexico.Conservation status (IUCN)Endangered (EN) (A1ce+2ce, B1+2c, C1+2a)Threat to humansHarmlessUsesAquarium: commercial More guppies & livebearersBold characodonCharacodon audaxBluetail goodeaAtaeniobius toweriButterfly splitfinAmeca splendensPoecilia wingeiMollyPoecilia sphenopsSouthern platyfishXiphophorus maculatusSee all guppies & livebearers SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026